Blogging the Dover Trial

By Ed Brayton

Posted September 28, 2005

Here's another excellent resource for timely updates on the Dover trial. The
ACLU of Pennsylvania has set up a blog with frequent updates on what is going on in the
courtroom. Jonathan Witt of the Discovery Institute is also blogging live from
the trial on the DI
blog. His post on Ken Miller's testimony yesterday was rather off the mark,
as one would expect. He makes the superficially compelling argument that Ken
Miller argued both that ID was not falsifiable and was falsified. But this
ignores a fairly obvious logical distinction. Witt writes:

In friendly questioning from the plaintiff, Miller asserted that the theory
of intelligent design was "not a testable theory in any sense" and so wasn't
science. Later, however, Miller argued that science has tested Michael Behe's
bacterial flagellum argument and falsified it, by pointing to a micro-syringe
called the Type III Secretory System, and arguing that it could have served as
a functional step on the gradual, Darwinian pathway to the full flagellar
motor.

Did the journalists covering the trial notice the contradiction? Miller
tried to provide a fig leaf for it, but the fig leaf was itself a
misrepresentation. Miller said Behe's argument was in every respect a negative
argument (and, further, that ALL the leading design theorists' arguments he
was aware of are purely negative, with nothing positive anywhere). Miller
conceded that Behe's irreducible complexity argument was testable, but said
Behe's inference to design doesn't follow from irreducible complexity because
Behe was committing the either/or fallacy—If not A (Darwinism), then it must
be B (design). Miller said there were, in principle, an infinite number of
other possible explanations, so jumping from a refutation of Darwinism to
design was illegitimate.

He's missing a crucial distinction by conflating Behe's argument for ID with
ID itself. The notion that an intelligent designer was involved is not in any
way falsifiable. There is no conceivable set of data that could falsify that
proposition. But specific arguments that purport to point to such a designer can
be falsified, and it's important to distinguish here between facts and theories.
Behe's argument offers both factual claims and a theoretical or explanatory
claim. It goes like this:

Factual claim: Some biochemical systems are irreducibly complex,
meaning that if you took out any single component of the system, the system
would fail to function.

Factual claim: Irreducibly complex systems could not have evolved
step by step because the intermediate or precursor systems would not have been
functional.

Explanatory claim: Therefore, when we find an irreducibly complex
system, we know that it must have been designed from scratch and came into
existence all in one step.

Only the explanatory claim is an explicit statement in support of ID, but one
can still falsify the argument if one shows that either of the two factual
claims it is based upon is false. For instance, when we look at Behe's example
of the blood clotting cascade, we can falsify it simply by looking at the first
factual claim. Is the blood clotting cascade irreducibly complex? The answer is
no. There are animals who lack one of the components of the system, yet their
blood clots just fine. Dolphins, for example, lack Hageman factor (or Factor
12). By Behe's definition of irreducible complexity, this should be impossible.
The fact that it's not shows that this is not, in fact, an irreducibly complex
system.

Likewise on the bacterial flagellum, Behe's favorite example of irreducible
complexity, the fact that one subset of the system works well for another
function shows that the second factual claim in Behe's argument is not
necessarily true. We have lots of examples in molecular biology of components
for one system being adapted or co-opted for use in a different system. Even
Behe would admit as much. Lots of examples, for instance, of a given gene
duplication resulting in the production of two proteins, one of which is then
coopted for a different function in a system it was not originally involved with
inside the organism. So when we see that the flagellum includes a subset that
functions well in a different type of system, we can reasonably infer that
perhaps it was coopted in exactly the same way. Add this to the fact that we in
fact have multiple different types of flagella at work in the bacterial world,
suggesting that rather than being irreducibly complex there are multiple
different ways to get to the same result, and you have good reason to think that
Behe's second example fails because the second factual claim may well not be
true.

So Miller is in fact correct when he says that ID is not falsifiable, while
specific arguments for ID have been falsified. He's also correct to say that
there is not positive theory of ID, only a set of negative arguments or
criticisms of evolution. As Miller points out, this is the either/or fallacy at
work - "if not evolution, therefore God". Witt tries to debunk this argument by
pointing to positive statements from Of Pandas and People, but these
are easily debunked. He writes:

"If experience has shown that a certain class of phenomena results from
intelligent causes and then we encounter something new but similar, we
conclude its origin also to be from an intelligent cause."

It seems a reasonable argument, but the analogy is very poor for one obvious
reason: we have no experience with supernatural designers. IDers love to make
this analogy between human designers and the "intelligent designer" and to
pretend that the "intelligent designer" doesn't necessarily have to be
supernatural, but that is completely false. Their own definition of ID shows
this to be false, as I've argued many times without refutation (including DI's John West,
who ignored it completely). The DI's own definition of ID says:

The theory of intelligent design holds that certain features of the
universe and of living things are best explained by an intelligent cause, not
an undirected process such as natural selection.

Their own definition combines biological ID with cosmological ID, which means
the designer is responsible not only for living things, but for creating the
universe itself. The DI's writings on cosmological ID make clear that when they
say "certain features of the universe", they mean the nature of the universe
itself - the nature of nature. This pretty much closes the door on
their mantra-like citation of aliens as possible "intelligent designers". If the
argument is that the universe was designed with the ability to sustain life,
invoking alien life as an explanation is clearly absurd - alien life would be an
effect of that universal design, just as human life is, not a cause of it.

(Incidentally, let me add that I have no problem whatsoever with the claim
that the universe is designed to support life. Indeed, this is something I agree
with. I am a deist and I do believe that the universe was created with the
attributes to allow life to begin, exist and evolve when the conditions are
right. But not only does this have little to do with whether evolution is true
or not, I would maintain that there is a tension between accepting cosmological
ID and rejecting evolution. As my friend and colleague Howard Van Till likes to
point out, the ID movement believes in a God who created the universe with the
ability to sustain life, but did so poor a job of it that he had to continually
intervene to make sure it happened.)

And I am not alone in making this argument. William Dembski himself has
admitted that the intelligent designer could not be natural but must be
supernatural, in an August 1998 article called The Act of Creation,
published on ARN:

The complexity-specification criterion demonstrates that design pervades
cosmology and biology. Moreover, it is a transcendent design, not
reducible to the physical world. Indeed, no intelligent agent who is
strictly physical could have presided over the origin of the universe or
the origin of life.

So the only "positive statements" of ID "theory" that Witt can come up with
are in fact weak inferences based upon a terrible analogy between objects
designed by human beings and objects allegedly designed by a supernatural being
unconstrained by the laws of nature. It is the invocation of the supernatural
that makes ID outside the realm of science. Science does not deal with
supernatural explanations, not because of an a priori rejection of the
supernatural, but for the very practical reason that there is no means of
testing such explanations, no means of distinguishing between true and false
explanations of that type.

And because the history of science clearly shows that phenomena that we once
believed could only be explained by the kindness or anger of God were eventually
explained, through science, in purely natural terms. Where once we could only
explain bad crops or disease as the result of God's anger with us, or good crops
and good health as proof of God's pleasure with us, we now know the full range
of environmental and microbial causes of those outcomes. Where once we could
only explain earthquakes or hurricanes as proof of God's judgement upon us, we
now understand the natural causes of such events well enough to predict them
with a high degree of accuracy.

And this points up exactly why supernatural claims are not falsifiable -
because no matter what the outcome, it can be ascribed to God's whims. Good
crops or bad crops, good weather or natural disaster, sickness or health, all
can be easily "explained" by reference to the whim of a supernatural being with
the power to manipulate nature. But because we didn't stop there, because we
didn't accept this unfalsifiable explanation and continued to search for solid
and testable explanations for these natural phenomena, we now have modern
medicine that has extended human lifespans greatly. We now have modern
agriculture that feeds billions, and modern seismology and meteorology that
saves countless lives through their ability to predict disasters before they
happen.

Science is ruthlessly practical. Give scientists an explanation that
works and they'll run with it. But explanations that invoke the
supernatural have never achieved anything in science, while rejecting those
claims and continuing to search for natural explanations has literally
transformed our world. Small wonder, then, that scientists - including that
sizable portion of them who do believe that God, and therefore supernatural
entities, does exist - insist upon continuing the search for natural
explanations rather than giving up and accepting the untestable and unknowable
as an explanation and thereby ending the search that has proven so fruitful in
the past.